Who do you think is strong enough to break his bones. Some candidates are Silver Age Superman, WW Hulk, Thor's Hammer etc.
Who/What can break Wolverine's Bones?
We don't know what it takes to break Wolverine's bones as far as strength goes. We know it can survive hits from upper tier heroes without even denting so you have to reach into higher powers like skyfathers and beyond. The only way known to break adamantium right now is molecular manipulation or a high powered magic source, but even then that is a special element in of itself and doesn't get a clear definition of what the power is doing to destroy it.
@Phaedrusgr: I believe he ripped the joints in between the vertebrae. And even if he did break the spine in 2, it isn't 616 Wolverine so it wouldn't count towards the main universe. Fun fact: 616's joints seem inseparable since Dracula, Ba'al (class 70-80) and even Hulk couldn't dislocate any joints when pulling him let alone tearing them apart.
@Phaedrusgr: Basically, yeah. Adamantium is supposed to be unmeltable once hardened and we have seen the poundings it can take. Classic Thor with all his might (so he said) performed a hammer swing with mjolnir to a small cylinder of the stuff and it hardly made a visible dent. We have seen the poundings Wolverine can take without his bones being dented like multiple strikes to the face from WWH. Adamantium is supposedly only altered through precise molecular rearrangement and from the way Wolverine gets bashed someone has to definitely be stronger than Hulk or Thor or if they have something that mess with the metals molecules or something like the previously mentioned Antarctic vibranium etc.
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